How to Prepare Your Oven for Roasting and Baking Season

Ovens can be a mystery. Put a turkey in, let it cook for a magic amount of time, and take it out, and it might be perfect—or it might not. 

Luckily there are a few things we can do to make sure our oven isn’t working against us, to make sure it’s ready to roast a turkey (and pie and vegetables).

Here are a few tips (and the science behind them) to prepare your oven:

Check that oven temp! 

Just because the display says “350° F” doesn’t mean that it’s true. Ovens can run hot or cool, sometimes by 20 to 30° F. If your oven is miscalibrated and heating to 330° F instead, the offset will make a huge, huge difference in your cooking. Foods won’t just take longer to cook—they’ll taste different. The two main browning reactions in cooking are temperature dependent, so a too-cold oven won’t create the rich flavors we associate with roasting. 

Snag a digital thermometer with a probe (a cable that’s a few feet long and can be left in the oven with the digital reader outside) and use it to check the oven by resting the probe on a center rack and taking a few temperature readings. Ovens cycle up and down in temperature—gas ovens, especially—so take a couple of readings over 10 to 15 minutes. If you can’t change the oven’s display to calibrate it, adjust the temperature that you dial in. That is, if your oven runs 20° F cool  and you want it to be at 350° F, then set it to 370° F.

Always use a probe thermometer when cooking fish and meats.   

The best way to guarantee great roasts, perfectly cooked fish, and juicy birds is to heat them to the right temperatures, ones that cause some of the fats to melt and some of the proteins to denature. For fish, this is somewhere between 120° F and 130° F; for meats, most of us prefer them cooked between 130° F and 150° F. Why not measure the temperature directly, instead of relying on a guesstimate with a timer? Tuck the probe into the food, run the cable out the oven door, and set the digital thermometer’s alarm to beep a few degrees under the target temperature. You’ll get consistent results time and time again. If your foods are overcooking, drop the target temperature a few degrees the next time.

Stash a pizza brick or a few oven-safe bricks on the lowest rack of your oven. 

This adds thermal mass to your oven—there’s more material to heat up and cool down. This means the oven will take longer to heat up, but when you go to add poultry or a roast into the oven, the temperature won’t drop as much, meaning faster cook times and better browning. Let your oven preheat for at least 30 minutes, even if it claims to be ready sooner. One experiment I did for the second edition of Cooking for Geeks used a thick stack of bricks, which added a full hour to the heating time. The improvement in both smaller temperature drop and faster cooking time were significant.

Clean your oven.

One important way that foods cook is by infrared radiation, the form of energy that you feel when sunlight hits your skin, and the inside of your oven is designed to normally bounce infrared radiation around. Splattered grease changes that, but cleaning your oven is the easy fix. Depending on how often you cook “splattery” food, clean your oven every few months. (If you can’t remember the last time you cleaned your oven, it’s probably time.) I find it easiest to run the oven’s cleaning cycle mode, which turns that grease into easily-swept-away ash, but a good scrubbing with a scouring pad works, too. If you are using your oven’s cleaning cycle, leave your pizza brick in the oven during cleaning—it’ll come out cleaner too!

Control for humidity, especially when roasting and baking. 

Higher humidity means more heat transfer, even at the same temperature. Depending on where you live, humid summers will cause foods to cook faster than they will in the dry of winter. The type of oven also matters: Gas ovens tend to maintain a standard rate of humidity as the gas combusts and displaces the air in the oven, while electric ovens start out drier and become more humid as water from the food being cooked evaporates and gets trapped. If your roasts are coming out dry on the outside, try covering them for the first half of cooking, using either aluminum foil or a container with a fitted lid. The baker’s trick of adding a pan of water on a lower rack can also help by increasing humidity.

Of course, there’s a lot more to turning out a great-tasting holiday meal than these quick oven tips, but these five tips are often overlooked, easy to do, and will help prevent some easy-to-fix problems. Here’s to a successful roasting season free of oven surprises.

This article originally appeared on November 4, 2015. We're re-running it because Thanksgiving's right around the corner (really!).

Photos by James Ransom; graph from Cooking for Geeks by Jeff Potter. Get the book here.